A product of the German company Brauniger, the variometer IQ-Basis is the most basic model of the IQ series. Nevertheless, it doesn't fail to surprise, here pleasantly, there unpleasantly, with some of its unusual functions and characteristics.
The instrument's LCD display is conceived so as to make a maximum amount of data directly visible without having to push any buttons. This allows for continuous monitoring of the averaging variometer, speedometer, altimeter, clock and battery status. The displayed functions lose nothing of their clarity. Changing data settings is also straightforward and, in comparison with the Flytec instrument, relatively simple.
Charging and Power Consumption
The instrument is powered by two AA batteries. It is possible to use every type of battery from alkaline to re-chargeable NiMH. There is a space for two reserve AAA batteries within the instrument as well, which however is not wired with connectors, nor does the on/off switch have a third position for reserve batteries. Power consumption while the instrument is in use fluctuates around 17mA and during acoustic signalization it climbs 20mA, which means that with fully-charged NiMH batteries, with a capacity of 1,100mAh, approximately 60 hours of operation. Using alkaline batteries extends this period by 2or 3 times. The specifications in the manufacturer's manual are needlessly humble, as they claim only about 80 hours of operation time. With the switch turned off the instrument uses 0.07mA. There is therefore no reason to remove them from the instrument for longer periods of inactivity.
Measures two independent altitudes with a precision of 1m. The first altitude is absolute - above sea level - harnessed with air pressure, and the second is relative, relating for example to the altitude of the runway or landing strip. Both altitudes can, surprisingly, be set directly by pressing the corresponding button, without having to switch to some setting mode.
The variometer shows the ascent or descent with a precision of 0.1m/s. IQ-Basis measures three different types of data by various methods. The Analog variometer displays the measured values with the aid of a circular indicator from -8m/s to +8m/s with an accuracy of 0.2m and with an adjustable sensitivity (reaction speed) from 1s to 3.6s. The Digital variometer is actually an averaging variometer with an integrated constant, adjustable within a range of 1s up to 30s. The measuring range of the digital variometer is -19.9m/s to +19.9m/s and its accuracy is 0.1m/s. The Acoustic variometer indicates ascent or descent by special acoustic signals, of which it is possible to set the volume in two degrees. And her we come to the first unpleasant surprise. The threshold of range of the descent warning signal, or sink alarm can be set comfortably from 0.1m/s up to -10m/s, but the threshold setting of acoustics for ascent cannot! It stays put at a value of +0.1m/s. A tough bite to chew for pilots who are used to adjusting the threshold settings of the acoustic signals at whim.
Following the attachment of an external sensor it is possible to measure the speed of movement in relation to the surrounding environment.
Also adjust the threshold of displacement of acoustic indication of a drop in speed below the set limit.
Measures temperature in degrees Fahrenheit or Celsius.
measures only two independent time data. Real Time determines the current date and time. The Stopwatch allows measurement of a time interval, which has taken place from its switch on. Here is another unpleasant surprise - the Stopwatch measures time to a precision of 1 minute, which maybe isn't a reason to be uneasy. However the date indicator is truly ready for the year 2000. The date not only is not shown in two-digit form, but, surprisingly clever, it doesn't show up at all! It's not necessary to add that you won't be flying on February 29 with this instrument. The IQ-Basis doesn't recognize this as a valid date!
holds data about the last ten flights made. It records maximum altitude reached, maximum over height, maximum climb and descent, maximum speed, duration and date of flight, without the year of course.
The IQ Basis does not allow for connection of any external devices other than a speed sensor. It therefore is unable to communicate with a computer or a GPS device, nor is it possible to hook up a printer.
With a growing ascent not only does the interval between sound signals decrease, (it beeps faster), but the tone also gets higher, which helps enable the pilot to detect even very small changes. Unfortunately the acoustic sensitivity of the instrument around zero is relatively small. It is hard not to remember the Alibi instrument in this instance, which on the other hand very roughly determines ascent above 5m/s.
A Pleasant Surprise For the End ?!
If we turn the instrument off while pressing the Memo button, a interesting function is activated, which is not mentioned in the manual. The foreign manual calls this function, somewhat grandly, "Weather Forecast". But a more accurate description would be "Pressure Tendence" over the last 48 hours.
When the instrument is thus turned off, it wakes up every hour for ten seconds and automatically records the atmospheric pressure. The memory register contains 48 values and works on the system FIFO, so that information on pressure for the past two days is always available. Of course the instrument cannot change its position over these two days, or more accurately, its altitude. Display of pressure tendencies isn't as comfortable and clear as on logarithmic, column indicators designed for this purpose such as the Flytec Weather Forecast, but the purpose is served. The pilot has at his disposal upon waking an overview of what took place with the atmospheric pressure overnight, which is obviously the most important thing to him at that moment …